It's been a huge season for Grey's Anatomy- killing off Derek Shepard (aka McDreamy) was a massive gambit for the series that, initially, paid off pretty well. Grey's Anatomy was once again on the tip of everybody's tongues- people were talking about it, Googling it, and (most importantly) watching it.

Now, a new rumor is potentially just as massive as seeing McDreamy's final moments- that Katherine Heigl might return to the Grey's Anatomy fold. Heigl initially played Izzie Stevens, one of the show's original characters, but left during the sixth season to spend more time with her family. But five years since her departure, is it time for Izzie's return?

According to the rumors, much of the reason for a potential Heigl return would be the stalling of her own career. None of her movies were particularly popular, and Heigl's political thriller State of Affairs was cancelled after just one season. Heigl is obviously in need of a career boost- and a return to Grey's would provide just that (so says the rumor, maybe not even a full-time role- just a few episodes here and there).

Heigl's even hinted about returning to Grey's in the past- "If they want me to return for an arc, I would love to know where Izzie is now. It's been a couple of years. I really hope she's succeeding somewhere." However, series creator Shonda Rhimes still harbors a grudge against Heigl- which might render all this Heigl talk a moot point.

It's worth noting that Grey's Anatomy's ratings have turned sour since killing off McDreamy- even a game-changer like that could hook fans for more than a week or two. A struggling show might just be the catalyst Rhimes needs to make amends with Katherine Heigl. Or maybe not. Either way, Grey's will return this fall, just like always.